Preheater and furnace-shield.



W. S. ROCKWELL PREHEATER AND FURNAGE SHIELD.

APPLIOATION FILED AUG.15, 1913.

Patented Nov. 18, 1913.

3 SHEETS-SHEET 1.

muy. 1.

W. S. ROCKWELL.

PREHEATER AND FURNACE smu). APPLIGATION FILED AUG.15,1913. 1,079,266.Patented Nov. 18, 1913.

3 SHEETS-SHEBT 2.

WALTER S. ROCKWELL, OF NEW YORKAN. Y.

PREHEATER AND FURNACE-SHIELD.

Speeification of Letters Patent.

Patented Nov. 18, 1913.

Application filed August 15, 1913. Serial No. ?84,912.

To all whom it may conce 'n Be it known that I, WALTER S. RocwnLL, acitizen of thetUnited States, residlng at 300 West One Hundred and SixthStreet,

New York, county of New York, and State of New York, have inventedcertain new and useful Improvements in Preheaters and Furnace-Shields,fully described and represented in the following specification and theaccompanying drawings, forming a part of the same.

The 'present invention relates to that class of furnaces used in heatingmetal for various purposes, as in forging, welding, bending, annealing,hardening, tempering, and other Operations. Such furnaces have a heatingchamber heated by suitable fuel, and provided with a so-calledworking-opening through which the metal to be heated is introduced andremoved, and such workingopening is left open and used as the outlet forall or a part of the Waste gases, when the metal is in bars whichproject through the opening during the heating operation, as in makingbeats upon the ends of rods for heading bolts, welding, &0. Suchworking-opening cannot be provided with a door where the bars projectoutwardly therefrom during the heating operation, and the fiaming gaseswhich escape at such opening necessarly create a very high temperaturearound the opening and cause great discomfort to the'operator whohandles the heated bars.

One object of the present invention is to utilize the waste heat of theescaping gsses to heat the air which is used in the conbustion of thefuel and thus heat tl'e chamber with less Consumption of fuel; andanother object of the invention is to combine with the preheater for theair a shield to protect the operator in great part from the heat of thewaste-gases, where they escape from the working-opening.

To protect the operator, shields of various kinds have been employedadjacent to the working-opening to intercept the heat rays; but thepresent invention provides an attachment for the front of a heating'furnace which not only intercepts the beat, but deflects the hot gasesinto direct contact with air-conduits which deliver the heated air tothe fuel.

lVhere coal rr coke is used as the tuel, the heated air is deliveredthereto to promote the combustion; but where liquid or gaseous fuel isused, the heated air is discharged wholly or in part through thefuel-burners to mingle with the fuel as it enters the furnace-chamber.

Sometimes where short portions of bars are to be heated, it is common tolocate such fuel-bvrners beneath the level of the bars; but where longbars are to be heated they re uire the support of the chamber-fl oor, anthe burners are located above such floor; but the operation of thepreheated air is the same in either case, to producethe requiredtemperature with less Consumption of fuel.

A typical form of the invention, for use adjacent to the wm-kin -openingof the furnace, consists of a shie fd which is combined withair-conduits in such a manner as to form a casing which is supportedupon the furnace front just above the furnace opening and through whichthe waste-gases may be conducted.

The air is preferably conducted in a tortuous path through thepreheater, to keep the air longer under the heating influence, and aseries of transverse pipes is therefore employed which are connected attheir opposite ends respectively by suitableheaders.

(last iron headers may be used, to the outer sidcs of which a shicld canbe attached which, with the h aders, forms a complete inclosure orcasing for the conduit-pipes, when fitted to the furnacc-front.

A blast-pipe is preferably provided at the bottom of the casing,directing an air-cun, rent toward the cscaping gascs to obstruct theirflow toward the operator and compel them to move upwardly through thecasing.

By attaching the headers to the furnace front the casing is whollyclosed and operates to hold the waste-gases close to the surfaces of theconduits so as to hoat the latter most efi'ectively.

The series of pipes is somewhat inclined to the vertical so that the hotgas may strike all the transverse pipes successively as it rises toescape from the top of the casing.

The series of condits is connected at one end to an air-supply-pipe, andat the' other end to one or more delivcry-pipes for conductingthe'heated air into contact with the burning fuel. WVith suchConstruction, the lower horizontal pipe of the conduits is provided withperforations upon its lower side 110 and the invention is not theretorelimited to the precise Construction shown in the drawing, but includesany such appliance 'providng a downward blast upon the escapng gases toarrest their outward movement; the conbination of a preheater andinclosig casing with the wall of the furnace wherevethe vaste-gasesescape, and the combination with a working-openin forming a gas-outlet,of a shield combine with a preheater to protect the operator froni thewaste-gases while utilizing their heat to heat the air for combustion.

Having thus set forth the nature of the invention what is claimed hereinis:

1. An attachment for metal-heating furnaces, comprisin a preheater and'shield consisting of airieating pipes with connections for the supplyand deliver of air, a non-conducting plate at one si e of such pipes andSecured thereto, and means for supporting the preheater' and shield uponthe outside of the furnace.

2. An attachment for metal-heating furnaces, comprising a preheater andshield consisting of a plurality of pipes connected together at theirends and provided with inlet and outlet for air, a plate attached tosuch pipes and provided With a layer of nonconducting material to form ashield, and means' for supporting the preheater and shield upon theoutside of the furnace.

3. An attachment for metal-heating furnaces, comprising a preheater andshield consisting of a plurahty of arallel pipes,

headers connected respectively to the opposite ends of such pipes andprovided with inlet and outlet for air, a plate attached to the headersand provided with a layer of non-conducting material to form a shield,and means for supporting'the headers upon the outside of the furnace.

4. The combination, with a metal heating furnace having a heatingchamber with an outlet for the waste gases, ofa casing ofnon-heat-conducting material supported adjacent to such outlet with thewaste gases conducted therethrough, and air conduits in the casn in thepath of the heated gases, such conc uits having inlet with connection toan air-blower and outlet delivering the heated air to the fuel duringthe combustion of the same.

5. In a metal heating furnace, the combination, with a furnace-fronthaving a heating-chamber with working-opening in such front from whichthe waste gascs may escape, of a shield of non-hoat conducting materialsupported adjacent to the furnacefront above such working-opening, witha vertical passageway between such shield and front through which thewaste gases may travel, and an air-blast-pipe supported above the saidopening at the bottom of the passageway, and directing an air-blast uponthe gases escaping from the said opening and Operating to deflect theminto said passageway.

6. In a metal-heating furnace, the combinatiom with a furnace-t'ront anda heating-chamber, with working-opening in such front from which thewaste gascs may escape, of 'a shield of non-heat-conducting materialsupported adja'cent to the front above said opening, forming a casinadjacent to such opening through whic the waste gases may travel,connected air-conduits in such casing with outlet deliverin the heatedair to the fuel of the furnace, an with inlet connected to a pipesupplying air under pressure.-

7.'In a metal-heating furnace, thecombination, with a furnace-front anda heating-chamber with working-opening in such front from which thewaste* gases may 35 escape, of a shield of non-heat-conducting materialsupported adjacent to the front above said opening, formng a casinadjacent to such opening through whic' the waste gascs may travel,connected air-conduits in such casing with outlet delivering the heatedair to the fuel of the furnace, the bottom Conduit being perforated a'ndthe air-blast therefrom directed against the waste gases to defiect themfrom the operator into the said casing, an air-supply-pipe connected tothe Conduit, and a valve in such supply-ppe controllin the supply of airto the blast-pipe, the con( uits, and the fuel.

8. In a metal-heating furnace, the combination, with a heating-chamberprovided with fluid-fuel-burners and having a working-opening at thefront ermitting the escape of waste gases theref om, of a preheatcrcasing above such opening, and ai'- conduits therein connected to thefuel-burners and supplying heated air thereto.

9. In a metal-heating turnace, the combination, with a heating chamberprovided with lud-fuel-burners and having a working-opening at the frontermtting the escape of waste gases there rom, of a preheater casingabove such opening, with horizontal air-conduits arranged in an inclinedseries therein transverse to the movement of the gases, and snpplyingheated air to the fuel-burners.

10. In a. metal-heating furnace, the conbination, with a heating-chambcrprovided with fluid-:fuel-burners and having a working-opening at thefront permitting the escape ot' waste gases thei-ofroni, of a preheatercasing above such opening with a non-leat-conducting shield upon itsouter side, and air-conduits therein connected to 1 the 'fucl-burnersand supplying heated air thereto.

11. lu a metal-heating furnace, the combination, with a-hcating-chamberprovided With fiuid-fuel-burners and having a work- 0

